Fastening unit for connecting thermally stressed components to each other

Abstract

A fastening unit for connecting a heat-generating body to a heat sink is provided. The fastening unit includes a retaining pin and a retaining element wherein the retaining pin is connected to a retaining head. The retaining pin extends through the retaining element and the retaining head contacts the retaining element. The retaining element is engageable upon a body of the heat sink so as to retain same in a fastening direction of the retaining pin. The retaining element is engageable laterally on the body of the heat sink, the retaining element having, on a side thereof for facing the body of the heat sink, a retaining groove extending in a longitudinal direction perpendicular to the fastening direction. In an assembled state for the fastening unit, at least one groove surface of the retaining groove of the retaining element contacts the body of the heat sink.

The invention claimed is: 
     
       1. Fastening unit for connecting a heat-generating body to a heat sink, the fastening unit comprising a retaining pin and a retaining element wherein the retaining pin is connected to a retaining head, the retaining pin extends through the retaining element, the retaining head contacts the retaining element, the retaining element engageable upon a body of the heat sink so as to retain same in a fastening direction of the retaining pin, the retaining element engageable laterally on the body of the heat sink, the retaining element having, on a side thereof for facing the body of the heat sink, a retaining groove extending in a longitudinal direction perpendicular to the fastening direction, wherein, in an assembled state for the fastening unit, at least one groove surface of the retaining groove of the retaining element contacts the body of the heat sink. 
     
     
       2. Fastening unit according to  claim 1 , wherein the retaining groove is formed in a V-shape by two groove surfaces, one groove surface being aligned parallel to a longitudinal axis of the retaining pin, another groove surface being inclined relative thereto, the two groove surfaces extending at an acute or obtuse angle to one another. 
     
     
       3. Fastening unit according to  claim 1 , wherein a base area of the retaining element is substantially rectangular. 
     
     
       4. Fastening unit according to  claim 1 , wherein the retaining element has a greater length in the longitudinally extending direction of the retaining groove than transversely to the longitudinally extending direction of the retaining groove. 
     
     
       5. Fastening unit according to  claim 1 , wherein the retaining element includes two retaining grooves, the retaining element having a structural symmetry about a centerline thereof so as to enable the retaining element to bear against first and second adjacent heat-generating bodies or heat sinks simultaneously. 
     
     
       6. Fastening unit according to  claim 5 , wherein at its center, to a side of the retaining pin, the retaining element has an elongated projection that extends perpendicularly to the retaining pin, the elongated projection having a further groove in a side thereof remote from the retaining head. 
     
     
       7. Fastening unit according to  claim 6 , wherein the further groove is V-shaped. 
     
     
       8. Fastening unit according to  claim 1 , wherein the retaining head engages in, and bears against, a recess of the retaining element. 
     
     
       9. Fastening unit according to  claim 8 , wherein the retaining head is cylindrical and the recess is of cylindrical shape, an end face of the retaining head thereby resting on an end face of the recess thus enabling a relative compensating movement about a common cylinder axis for the retaining head and the recess of the retaining element. 
     
     
       10. Fastening unit according to  claim 8 , wherein the retaining head is at least partially spherical on a side facing the recess, the recess has a partially spherical shape adapted to conform to a portion of the retaining head so that cooperative engaged spherical surfaces permit a compensating movement relative to one another. 
     
     
       11. Fastening unit according to  claim 1 , wherein the retaining pin has a thread at an end remote from the retaining head, the thread adapted to engage a thread in a bore of the heat sink or of the heat-generating body. 
     
     
       12. Fastening unit according to  claim 1 , wherein at an end remote from the retaining head, the retaining pin has at least one detent adapted to engage an undercut of a bore in the heat sink or of the heat-generating body, and the retaining pin is slotted in a region of the end remote from the retaining head. 
     
     
       13. Fastening unit according to  claim 1  in operative combination with a heat sink and a heat-generating body, the heat-generating body comprising a power semiconductor. 
     
     
       14. Fastening unit according to  claim 1  in operative combination with a heat sink and a heat-generating body, the heat sink comprising an air cooled heat sink and/or a liquid cooled heat sink. 
     
     
       15. Fastening unit according to  claim 1 , wherein the retaining head comprises a thermally and/or an electrically insulating material, or an electrically conductive material. 
     
     
       16. In operative combination, at least two fastening units according to  claim 1  for connecting a heat sink and a heat-generating body to each other, wherein the at least two fastening units are mounted opposite one another on an edge of the heat-generating body or the heat sink so as to form a floating bearing. 
     
     
       17. In the operative combination according to  claim 16 , wherein in a mounted state, the retaining grooves of the fastening units are aligned parallel to each other.